Fiber Polymer Composites Research Articles

In‐situ fabrication of poly‐l‐lactide & its application as a glass fiber polymer composites using resin transfer molding

In‐situ fabrication of poly‐l‐lactide & its application as a glass fiber polymer composites using resin transfer molding

Upcycling end-of-life carbon fiber in high-performance CFRP composites by the material extrusion additive manufacturing process

Each year, a significant amount of waste is produced from carbon fiber polymer composites at the end of its lifecycle due to extensive use across various applications. Utilizing regenerative carbon fiber as a feedstock material offers a promising and sustainable approach to additive manufacturing based on materials. This study proposes the additive manufacturing of recycled carbon fiber with a polyamide-12 polymer composite. Filaments of recycled carbon fiber-reinforced polyamide-12 (rCF-PA12) with different recycled carbon fiber contents (0%, 10%, and 15% by weight) in the polyamide-12 matrix are developed. These filaments are utilized for 3D printing of specimens by using various infill density parameters (80% and 100%) on a fused deposition modeling 3D printer. The study examined how the fiber content and infill densities influenced the flexural performance of the printed specimens. Notably, the part containing 15 wt% recycled carbon fiber (rCF) composites showed a significant improvement in flexural performance due to enhanced interface bonding and effective fiber alignment. The results indicated that reinforcing the printed part with 10% and 15 wt% recycled carbon fiber (rCF) improved the flexural properties by 49.86% and 91.75%, respectively, compared to the unreinforced printed part under the same infill density and printing parameters. The investigation demonstrates that the additive manufacturing-based technique presents a potential approach to use carbon fiber-reinforced polymers waste and manufacture high-performance engineering, economic, and environmentally friendly industrial applications with the complicated design using different polymer matrices.

Structural response of glass fiber-polymer composite bending-active elastica beam under long-term loading conditions

Bending-active elastica beams represent structural members which are initially installed as straight beams and then bent into arched shapes by applying horizontal displacements to one support. Designing such members for permanent structures made of fiber-polymer composites involves complex viscoelastic responses, which have not yet been thoroughly investigated. An experimental investigation of medium-scale bending-active elastica beams, consisting of pultruded glass fiber-polymer composite profiles, was thus conducted to investigate the long-term structural behavior of such members under imposed sustained bending and axial compression. The results revealed that viscoelastic responses are based on an interaction of stress relaxation and creep with their effects increased with increasing bending degree and time of exposure to sustained strains and stresses. The imposed horizontal displacement to one of the supports to maintain the bent beam shape induced sustained bending stresses in the beam. Beneficial relaxation of these stresses occurred with relaxation predicted to reach 12 % during a targeted 50-year design service life. Furthermore, the likelihood of the curved beam exhibiting in-plane deformations under sustained stresses enabled creep to occur simultaneously, with associated in-plane creep deformations and strength reduction. While creep deformations remained insignificant, progressive creep rupture occurred at highest bending degrees, exhibiting sequential creep rupture in the outer combined mat layers, delamination, crack opening and final fiber failure. Creep rupture can be prevented by postponing crack initiation in the combined mat layer beyond the targeted design service life. This can be achieved by limiting the bending degree to 50 % of the bending degree at which short-term crack initiation occurs.

Wet-Spinning Carbon Nanotube/Shape Memory Polymer Composite Fibers with High Actuation Stress and Predesigned Shape Change.

Actuators based on shape memory polymers and composites incorporating nanomaterial additives have been extensively studied; achieving both high output stress and precise shape change by low-cost, scalable methods is a long-term-desired yet challenging task. Here, conventional polymers (polyurea) and carbon nanotube (CNT) fillers are combined to fabricate reinforced composite fibers with exceptional actuation performance, by a wet-spinning method amenable for continuous production. It is found that a thermal-induced shrinkage step could obtain densified strong fibers, and the presence of CNTs effectively promotes the tensile orientation of polymer molecular chains, leading to much improved mechanical properties. Consequently, the CNT/ polyurea composite fibers exhibit stresses as high as 33MPa within 0.36 s during thermal actuation, and stresses up to 22MPa upon electrical stimulation enabled by the built-in conductive CNT networks. Utilizing the flexible thin fibers, various shape change behavior are also demonstrated including the conversion between different structures/curvatures, and recovery of predefined simple patterns. This high-performance composite fibers, capable of both thermal and electrical actuation and produced by low-cost materials and fabrication process, may find many potential applications in wearable devices, robotics, and biomedical areas.

Environmental sustainability and waste conversion of Prosopis juliflora fibre-reinforced ZnO nanofiller particulates PLA composite- mechanical and thermal analysis

The presence of large quantities of Prosopis juliflora (PJ) fibers in natural habitats presents substantial threats to the environment and economies of numerous developing countries. Utilizing natural fibers in polymer composites can effectively enhance their characteristics. The primary objective of this study is to create a composite material by combining Prosopis Juliflora (PJ) fiber with a polylactic matrix that has been combined with zinc oxide nanofillers. The fabrication process will involve the hand layup technique. In order to have a comprehensive understanding of the mechanical characteristics, thermal behavior, and thermal stability of the PJ composite, it is necessary to undertake additional investigations. The results showed that the inclusion of zinc oxide filler enhanced the tensile strength (67.29 MPa), flexural strength (64.27 MPa), compressive strength (56.79 MPa), and impact energy (34 J) in sample S5. Additionally, the thermal properties, including thermal conductivity, thermal expansion, and short-term heat resistant capacity, were also improved by the addition of zinc oxide filler in sample S5. The deterioration temperature of the PJ composite was determined to be between 312 and 342 °C using thermogravimetric analysis. The failure mode of the PJ composite was investigated using scanning electron microscopy.

Enhancement of mechanical and structural characteristics through the hybridization of carbon fiber with Cordia‐dichotoma/polyester composite

AbstractSingle fiber polymer composites containing either natural or artificial fibers may not deliver the desired characteristics. The current study used the hand‐layup technique to make a hybrid composite by incorporating the natural fiber, Cordia‐dichotoma (CD) and artificial fiber, carbon fibers (CF) in a polyester matrix and compressing the mixture for the desired size. The current study investigates the influence of carbon fiber loading (0, 5, 10, and 15 wt%) on the mechanical, structural, and crystalline properties of CD/polyester composites keeping the total fiber loading at 20 wt%. Mechanical properties are investigated with a universal testing machine, and impact strength using Izod impact apparatus. Better mechanical properties (tensile strength‐457.38 MPa; flexural strength‐290.09 MPa and impact strength‐346.46 J/m) were obtained for the pure carbon fiber composite arranged in four layers (CF/CF/CF/CF), followed by hybrid composite (CF/CD/CD/CF) (tensile strength‐319.24 MPa; flexural strength‐253.03 MPa and impact strength‐291.34 J/m) whereas pure CD fiber (CD/CD/CD/CD) composite yielded the lowest values (tensile strength‐117.96 MPa; flexural strength‐164.99 MPa and impact strength‐118.11 J/m). Composites undergo hybridization, which improves their mechanical properties, lowers their cost, and makes them more environmentally friendly. The characteristics of the specimens were examined using Fourier Transform Infrared Spectroscopy (FTIR), X‐ray Diffraction Analysis (XRD), Atomic Force Microscope (AFM), and Scanning Electron Microscopy (SEM). According to findings, crystallinity index is increased from 77.94% for CD/CD/CD/CD composite and increased to 78.21% for CF/CD/CD/CF composite. Highest crystallinity index of 82.46% was obtained for CF/CF/CF/CF composite. These hybrid composites may be used for applications involving medium loads.Highlights In this study, Cordia‐dichotoma natural fibers are extracted and treated with alkali (NaOH) to reduce the biodegradability. To lower the cost and enhance mechanical and biodegradable properties Carbon and cordia‐dichotoma fibers have been hybridized. Mechanical Properties such as tensile, flexural and impact properties are evaluated for the prepared hybrid composites. Hybrid composites were analyzed using FTIR, AFM, XRD, and SEM to assess their suitability to various applications.

Comparative study on shape memory, mechanical, and thermomechanical properties of multi‐walled carbon nanotubes and graphene nanoplatelets modified bidirectional (twill) carbon fiber polymer composites

AbstractThe research conducts a comparative analysis of epoxy/bi‐directional (twill) carbon fiber three‐phase shape memory hybrid composites modified with MWCNT and GnP, examining their mechanical, thermomechanical, and shape memory properties. Fabrication involves preparing nanoparticle‐modified epoxy nanocomposites through ultrasonication followed by hand layup technique. The findings revealed that the modified composites achieved their optimal performance at a 0.6 wt% concentration of nanoparticle, with the tensile strength and modulus increasing by 33.59% and 23.47% for 0.6 wt% MWCNT composite and by 45.94% and 25.61% for 0.6 wt% GnP composite. GnP‐modified composites outperformed MWCNT ones due to GnP's sheet structure aligning parallel to the load and larger surface area facilitating enhanced interaction with the matrix. Despite polymer modification, the shape recovery ratio values remained high, with 98.92% for unmodified composite, 97.72% for 0.6 wt% MWCNT composites, and 97.12% for 0.6 wt% GnP modified composites, all exceeding 90%, indicating no compromise in performance.

The impact of various curing methods on the curing process of polymer-fiber composites analyzed using analytical approach

Ti/Gf/Cf represents a novel form of hybrid fiber metal laminates (HFMLs) that successfully blend the benefits of titanium alloy, glass fiber reinforced plastic (GFRP), and carbon fiber reinforced plastic (CFRP). These materials have garnered attention in the field of engineering due to their exceptional levels of stiffness, strength, and shear resistance. The quality of HFMLs during the curing process was significantly impacted by the chosen curing method. Moreover, the use of multiple types of fibers complicated the optimization of curing parameters in HFMLs. A comprehensive study was conducted using a multi-physics field coupling finite element method to investigate the impact of various curing methods on the development of temperature distribution, curing degree, and curing stress in HFMLs during the curing process. By integrating thermal transmission equations, curing kinetics, and viscoelastic mechanical models, a detailed curing simulation model was established. Increasing the cooling rate from 1 °C to 5 °C was shown to raise the maximum curing stress by 4.7 MPa. Additionally, higher curing temperatures were found to induce internal curing stress due to variations in thermal properties. Insufficient insulation times were observed to exacerbate non-uniform temperature distribution and curing degree fields in HFMLs, potentially leading to increased internal stress. To mitigate the generation of large residual stress, it is recommended to lower the heating and cooling rates, reduce curing temperatures, and extend the insulation time appropriately during the curing process of HFMLs. The primary goal of this research was to accurately predict the evolution of curing parameters in HFMLs under different curing regimes, which were impacted by the chosen curing method. The results of the study demonstrated that rapid changes in temperature during heating and cooling stages can lead to uneven curing, resulting in the accumulation of residual stress within the laminates.

Optimization of microwave-produced coal-derived char insulation foam using response surface methodology

A new char-based insulation foam (CIF) is developed using coal-derived pyrolysis char (PC) and lignin, a paper and pulp industry byproduct. In this study, CIF is prepared by adopting the microwave method and Response Surface Methodology (RSM) is utilized to optimize predictions about the properties such as thermal conductivity, foam texture, compressive strength, and pore distribution of CIF. The three independent variables including percent char content, lignin/char ratio, and foaming agent/polyol ratio are considered in the RSM methodology. The face-centered central composite design is selected to obtain 17 test runs. Optimization of the predicted responses is performed to find the recipe considering a composite desirability function. Confirmatory test results show agreement between the predicted and observed values, with the percent error ranging from 0.00 % to 11.35 %, thereby confirming the accuracy of the prediction equations. The optimized CIF exhibits a thermal conductivity of 0.0633 W/m.K and a compressive strength of 695 kPa making it comparable to or better than traditional building insulation products such as fiber insulation, polymer composite, particle board, and ceramic glass foam. Therefore, this new CIF has the potential to be used as an energy-saving insulation material for building envelopes.

Lignocellulose sustainable composites from agro-waste Asparagus bean stem fiber for polymer casting applications: Effect of fiber treatment

In the past decades, lignocellulose fibers have attracted significant attention due to their low density, environmental friendliness, and biodegradability. Consequently, researchers are intensifying their efforts to explore the potential of lignocellulosic fibers as sustainable alternatives to synthetic fibers in polymer composites. Among various natural fibers identified as potential reinforcements, agro-waste from the Asparagus Bean stem (ABS) which has been discarded as landfill after harvest has emerged as a promising source of lignocellulose fibers for promoting sustainability. This study investigates the reinforcement suitability of ABSF in polymer matrices. A water-retting process was used for extraction, followed by treatment with a 5 % alkali solution. Cellulose content was enhanced to 65 wt%, and fiber density increased to 1.13 g/cm3 after chemical treatment. Thermogravimetric analysis indicated improved thermal stability of the treated fibers up to 247 °C. Morphological analysis showed increased surface roughness and impurity removal. To evaluate the reinforcing effect of the chemical treatment, epoxy composites with 10 wt% reinforcement were developed. The mechanical properties of these composites improved significantly, with more than 1.1 times when used alkali-treated ABSF as reinforcement. Flexural properties were substantially enhanced, with flexural strength increasing from 90.53 MPa to 122.71 MPa and flexural modulus from 2.41 GPa to 2.95 GPa due to better fiber-matrix interaction and removal of weak, amorphous constituents. The primary objective of this study is to demonstrate that ABSF is a viable alternative raw material for composite reinforcement, suitable for developing lightweight structural applications.

A Comprehensive Review of Recent Developments on the Natural Fiber Reinforced Polymer Matrix Composites for Automotive and Sports Application: Materials, Processes and Properties

Now a days, the world has been evolving and adapting to advance technology; as a result, the development and expansion of Composite materials have been growing day by day.. Natural fibres are a feasible and eco-friendly alternative to synthetic fibres for polymer composite reinforcing. Materials are attractive because they are economical, environmentally friendly, abundant in nature, and have mechanical properties[60]. Natural fibres are given first priority above all other types of fibres due to their appealing qualities include biodegradability, minimum cost, environmental friendliness, high strength-to-weight ratio in engineering goods, and low health risks. An overview of recent trends in physio mechanical characteristics, thermal properties, morphological behaviour, surface treatment, design optimisation with the ANOVA technique, the effect of Mercerization and SEM analysis, microstructural interfacial adhesion, and the various methodologies used to measure these properties. Keywords: Natural fiber polymer composites, Physio mechanical properties, SEM Analysis, Thermal properties, ANOVA technique, Applications.

Analysis of thermomechanical and dynamic characteristics of treated saccharum munja fiber polymer composite

Analysis of thermomechanical and dynamic characteristics of treated saccharum munja fiber polymer composite

Capacitive Sensors Based on Recycled Carbon Fibre (rCF) Composites.

Recycled carbon fibre (rCF) composites are increasingly being explored for applications such as strain sensing, manufacturing of automobile parts, assistive technologies, and structural health monitoring due to their properties and economic and environmental benefits. The high conductivity of carbon and its wide application for sensing makes rCF very attractive for integrating sensing into passive structures. In this paper, capacitive sensors have been fabricated using rCF composites of varying compositions. First, we investigated the suitability of recycled carbon fibre polymer composites for different sensing applications. As a proof of concept, we fabricated five touch/proximity sensors and three soil moisture sensors, using recycled carbon fibre composites and their performances compared. The soil moisture sensors were realised using rCF as electrodes. This makes them corrosion-resistant and more environmental-friendly, compared to conventional soil moisture sensors realised using metallic electrodes. The results of the touch/proximity sensing show an average change in capacitance (ΔC/C~34) for 20 mm and (ΔC/C~5) for 100 mm, distances of a hand from the active sensing region. The results of the soil moisture sensors show a stable and repeatable response, with a high sensitivity of ~116 pF/mL of water in the linear region. These results demonstrate their respective potential for touch/proximity sensing, as well as smart and sustainable agriculture.

Advancements in chemical modifications using NaOH to explore the chemical, mechanical and thermal properties of natural fiber polymer composites (NFPC)

Abstract Increasing environmental awareness and concerns about global warming have resulted in a significant demand for sustainable and eco-friendly resources, such as naturally available fibers, that can be suitable alternatives to petroleum/synthetic materials such as glass, carbon and Kevlar in reinforced composites. The exploration of natural fibers as reinforcements in composites is increasing in popularity, particularly in the development of transport and household components. However, natural fibers also have a few limitations that should be addressed appropriately, including lack of compatibility between fiber-matrix, fiber swelling, excess absorption of moisture, resistance to chemicals and fire. Consequently, various processes have been used to improve the fiber surface, to obtain a better fiber–matrix interface. The primary objective of this work is to review the impact that a 5 % NaOH (sodium hydroxide) treatment has on the chemical, mechanical, and thermal properties of natural fiber-reinforced composites (NFRC).

Hybrid recycling methods for fiber reinforced polymer composites: A review

Fibrous polymer composites are integral materials utilized in various sectors due to their unparalleled material properties. However, their widespread application has led to significant volumes of end-of-life material, necessitating sustainable disposal strategies. Conventional disposal methods, landfilling, and incineration exhibit shortcomings in both fiber recovery efficiency and environmental impact. Conversely, recycling presents a viable avenue for fiber recovery, facilitating its reuse in composite fabrication alongside allied industries like construction. This article provides a comprehensive examination of mechanical, thermal, and chemical recycling methods tailored for fibrous composites made of thermoset resins. In addition to traditional approaches, hybrid techniques emerge as compelling recycling prospects, amalgamating various traditional methods to enhance overall process efficiency while mitigating the limitations. This article stands out for its in-depth exploration of the intricate methodologies underpinning hybrid recycling methods. The article also delineates the range of products produced from recycling, encompassing fibers, liquids, and gaseous byproducts. In addition, a dedicated section outlines the potential applications of recovered fibers within the composite industry and their integration into cutting-edge additive manufacturing processes. Through a holistic examination of recycling strategies and their downstream implications, this article underscores the imperative for sustainable practices in the utilization and management of fibrous polymer composites.

Functionalised Fibres as a Coupling Reinforcement Agent in Recycled Polymer Composites.

This study addresses the structure-property relationship within the green concept of wood fibres with cellulose nanofibre functionalised composites (nW-PPr) containing recycled plastic polyolefins, in particular, polypropylene (PP-r). It focuses especially on the challenges posed by nanoscience in relation to wood fibres (WF) and explores possible changes in the thermal properties, crystallinity, morphology, and mechanical properties. In a two-step methodology, wood fibres (50% wt%) were first functionalised with nanocellulose (nC; 1-9 wt%) and then, secondly, processed into composites using an extrusion process. The surface modification of nC improves its compatibility with the polymer matrix, resulting in improved adhesion, mechanical properties, and inherent biodegradability. The effects of the functionalised WF on the recycled polymer composites were investigated systematically and included analyses of the structure, crystallisation, morphology, and surface properties, as well as thermal and mechanical properties. Using a comprehensive range of techniques, including X-ray diffraction (XRD), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), zeta potential measurements, and dynamic mechanical analysis (DMA), this study aims to unravel the intricate interplay of factors affecting the performance and properties of the developed nanocellulose-functionalised wood fibre-polymer composites. The interfacial adhesion of the nW-PPr polymer composites, crystallisation process, and surface properties was improved due to the formation of an H-bond between the nW coupling agent and neat PP-r. In addition, the role of nW (1.0 wt%) as a nucleating agent resulted in increased crystallinity, or, on the other hand, promoted the interfacial interaction with the highest amount (3.0% wt%, 9.0% wt%) of nW in the PP-r preferentially between the nW and neat PP-r, and also postponed the crystallisation temperature. The changes in the isoelectric point of the nW-PPr polymer composites compared to the neat PP-r polymer indicate the acid content of the polymer composite and, consequently, the final surface morphology. Finally, the higher storage modulus of the composites compared to neat r-PP shows a dependence on improved crystallinity, morphology, and adhesion. It was clear that the results of this study contribute to a better understanding of sustainable materials and can drive the development of environmentally friendly composites applied in packaging.

Spacesuit Textiles from Extreme Fabric Materials: Aromatic Amide Polymer and Boron Nitride Nanotube Composite Fiber for Neutron Shielding and Thermal Management

Spacesuit Textiles from Extreme Fabric Materials: Aromatic Amide Polymer and Boron Nitride Nanotube Composite Fiber for Neutron Shielding and Thermal Management

Fibre geometries and their contribution to the global unidirectional tensile properties of enset fibre-reinforced epoxy composites

This study investigated the potential forms of enset fibres and their tensile properties. Microscopic images of the fibre cross-section were collected, and image analysis was carried out in MATLAB. As a result, four distinct fibre shapes were identified and their likelihood of occurring as well as- their area contribution to the fibre bundle were determined. These fibres have distinct tensile strength, Young’s modulus, and strain-to-failure values, distinguishing the strongest and weakest fibres. The strength distribution of these fibre shapes does not conform to the Weibull theory. However, it follows the scenario that fibres with the biggest perimeter-to-area ratio provide the weakest values and vice versa. This shows that the tensile properties of fibres are influenced not only by their material properties but also by their geometric shape. As a result, fibres of different shapes contribute differently to the global tensile properties of the fibre-polymer composites.

Mechanical behavior of banana fiber polymer composite

Mechanical behavior of banana fiber polymer composite

Fabrication and Characterization of Natural Fiber-Polymer Composites for Prosthesis Socket Application

ABSTRACT A natural fiber-reinforced composite from a locally available false banana plant is developed for a prosthesis socket application. Four batches of composite samples are fabricated by arranging the longitudinal uniformly distributed unidirectional false banana fibers in four orientations (0°, 90°, ±45°, 0°/90o). The composites’ mechanical and physical properties, such as tensile strength, compression strength, flexural strength, impact resistance, and the effect of chemical treatment on water absorption, are investigated. The results are compared with E-glass fiber-reinforced polymer matrix composite. The false banana fiber-polymer composites with a 0° fiber orientation have a tensile strength of 86.81 MPa, less than 9% lower than E-glass-fiber composites (95.44 MPa), and an impact resistance of 6.25 J, 10% higher compared to the E-glass fiber polymer composites (5.70 J). In addition, the treated false banana fiber-polymer composite absorbed 70% less water than the untreated false banana fiber-polymer composite. It is observed that the fiber treatment has increased the polymer–fiber interaction and the interface strength of the false banana fiber-polymer composites.